Rennes retain hope over Mornar
Mornar is being chased by the Ligue 1 outfit, who want to land the Croatia international on a season-long loan deal.
The 30-year-old has failed to establish himself as a first choice at Fratton Park following his £500,000 switch from Anderlecht in January.
He started just three Premiership games for Pompey and is being offered regular football with Rennes.
Fellow French side Lens had also been keen on the bulky attacker but Rennes are optimistic their pursuit will prove successful.
They have been locked in lengthy negotiations with their Portsmouth counterparts and Rennes officials are aiming to tie up the deal by Thursday.
Mornar has two years remaining on his contract at Fratton Park but is likely to relish the prospect of enhanced opportunities with Rennes.
Meanwhile, Rennes have handed a trial to Australian goalkeeper Scott Higgins.
The 26-year-old has, most recently, played for Brisbane Strikers and is aiming to impress the club's coaching staff.